CN105699913B - Power source loads test device - Google Patents
Power source loads test device Download PDFInfo
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- CN105699913B CN105699913B CN201610012915.3A CN201610012915A CN105699913B CN 105699913 B CN105699913 B CN 105699913B CN 201610012915 A CN201610012915 A CN 201610012915A CN 105699913 B CN105699913 B CN 105699913B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/40—Testing power supplies
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- Testing Electric Properties And Detecting Electric Faults (AREA)
Abstract
A kind of power source loads test device, dynamic load test is carried out for power supply tested to one, the power source loads test device includes the master controller, function generator and the current detection circuit that are electrically connected successively, and the function generator is for one square-wave signal of output；Described draw carries the output current that circuit is used to dynamically change the tested power supply according to the square-wave signal；The current detection circuit is also electrically connected to the master controller, the current detection circuit is used for the slope that the master controller is coordinated to detect the output current, the master controller is used to the slope of the output current detected and a default slope value being compared, and the function generator is accordingly controlled to adjust the square-wave signal according to comparison result, until the slope of the output current is equal with the default slope value.
Description
Technical field
The present invention relates to a kind of power source loads test device more particularly to a kind of power source loads tests for computer VRM
Device.
Background technology
The VRM Voltage Regulator Module (Voltage Regulator Module, VRM) of computer in actual use, institute's band
Load is usually dynamic load, that is, the load of VRM changes at any time, and correspondingly, the output current of VRM is also with the change of load
Change and be in dynamic change.For example, computer, when entering certain games, the load of VRM institutes band can significantly increase, correspondingly
The output current of VRM also significantly increases.
When being tested into Mobile state VRM, generally an electronic load, the electronic load are connected in the output terminal of VRM
The dynamic load of VRM is tested in the output current realization for changing VRM by simulating actual use situation.VRM is tested into Mobile state
When, under the action of electronic load, the waveform of output current can generally be reduced to square-wave waveform shown in FIG. 1, the output of VRM
The rise time that electric current rises to I1 from 0 is t1, wherein, the drawing of the slope of output current, i.e. electronic load carries slope and is：I1 with
The ratio of rise time t1.According to the difference of load, the drawing load slope of VRM is also different, and sometimes, it is oblique that VRM needs larger drawing to carry
Rate loads to drive.
The drawing of current electronic load carries slope generally in 1A/ μ s or so, and is fixed, can not meet certain VRM
To the larger demand for drawing load slope.
Invention content
In view of the above-mentioned problems, provide the larger power source loads test device for drawing load slope it is necessary to provide a kind of.
A kind of power source loads test device carries out dynamic load test, including electrically connecting successively for power supply tested to one
The master controller that connects, function generator, draw carry circuit with, current detection circuit, be electrically connected to being used for for the master controller
The display of the keyboard circuit of the default slope value of input and the default slope value of the display input, the function generator are used for
Export a square-wave signal；Described draw carries the output electricity that circuit is used to dynamically change the tested power supply according to the square-wave signal
Stream；The current detection circuit is also electrically connected to the master controller, and the current detection circuit is used to coordinate the master control
Device processed detects the slope of the output current, and the master controller is used for the slope of the output current detected and one in advance
If slope value is compared, and the function generator is accordingly controlled to adjust the square-wave signal, Zhi Daosuo according to comparison result
The slope for stating output current is equal with the default slope value.
Power source loads test device of the present invention carries out the waveform of square-wave signal by main controller controls function generator
It adjusts, the drawing so as to accordingly adjust the power source loads test device by drawing load circuit carries slope, so as to obtain as needed
It obtains larger drawing and carries slope.In addition, according to the different default slope values that keyboard circuit inputs, the power source loads test device
It can also accordingly obtain different drawings and carry slope, therefore, there is preferable versatility.
Description of the drawings
Fig. 1 is output current wave figures of the existing VRM when being tested into Mobile state.
Fig. 2 is the functional block diagram of the power source loads test device of better embodiment of the present invention.
Fig. 3 is the circuit diagram of power source loads test device shown in Fig. 2.
Main element symbol description
Power source loads test device 100
VRM 200
Master controller 10
Function generator 20
It draws and carries circuit 30
Current detection circuit 40
Enabled circuit 50
Keyboard circuit 60
Display 70
Output current Io
Current detecting pin P1
Controlling switch P2
Voltage follower U1
Operational amplifier U2
First MOSFET Q1
NPN type triode Q2
PNP type triode Q3
2nd MOSFET Q4
Load resistance R0
Filter resistance R1
Current-limiting resistance R2-R8, R10
Feedback resistance R9
Filter capacitor C1
In-phase input end 1,5
Inverting input 2,6
Output terminal 3,7
Control terminal 4,8
Grid g1, g2
Source electrode s1, s2
Drain d1, d2
Base stage b1, b2
Collector c1, c2
Emitter e 1, e2
Following specific embodiment will be further illustrated the present invention with reference to above-mentioned attached drawing.
Specific embodiment
It is carried out referring to Fig. 2, the power source loads test device 100 of better embodiment of the present invention is used for the tested power supply to one
Dynamic load is tested.In the present embodiment, by the tested power supply for the present invention will be described for a VRM200.
Power source loads test device 100 includes master controller 10, function generator 20, draws load circuit 30, current detecting electricity
Road 40, enabled circuit 50, keyboard circuit 60 and display 70.Function generator 20 is for one square-wave signal of generation；It draws and carries electricity
Road 30 is used to dynamically change the output current of VRM200 according to the square-wave signal；Current detection circuit 40 is used to coordinate master control
Device 10 processed detects the output current Io of VRM200, i.e. load current, so as to obtain the slope of output current Io；The master controller
10 for the slope of output current Io and a default slope value to be compared, and are occurred according to the corresponding control function of comparison result
Device 20 adjusts the waveform of the square-wave signal, until the slope of output current Io is equal with the default slope value.
Also referring to Fig. 3, master controller 10 includes the current detecting pin P 1 for being electrically connected to current detection circuit 40
And it is electrically connected the controlling switch P2 of enabled circuit 50.
Load circuit 30 is drawn to include voltage follower U1, the first mos field effect transistor (Metal-
Oxide-Semiconductor Field-Effect Transistor, MOSFET) Q1, load resistance R0, filter resistance R1,
Current-limiting resistance R2-R5 and filter capacitor C1.Voltage follower U1 include in-phase input end 1, inverting input 2, output terminal 3 with
And control terminal 4.The in-phase input end 1 of voltage follower U1 is electrically connected to function generator 20 by current-limiting resistance R2, is used for
Receive the square-wave signal；Inverting input 2 passes sequentially through filter resistance R1 and filter capacitor C1 is electrically connected to output terminal 3；
Output terminal 3 is electrically connected to the grid g1 of the first MOSFET Q1 by current-limiting resistance R3；Control terminal 4 is electrically connected to enabled electricity
Road 50.The source electrode s1 of first MOSFET Q1 is grounded by load resistance R0, and source electrode s1 is also electrically connected to voltage follower U1's
Inverting input 2；The drain electrode d1 of first MOSFET Q1 is electrically connected to the output terminal of VRM200.In the present embodiment, source electrode
S1 is electrically connected the inverting input 2 of voltage follower U1 by current-limiting resistance R5.Current-limiting resistance R5 is used to prevent voltage follow
Electric current on the inverting input 2 of device U1 impacts the test of the output current Io of VRM.
Voltage on the output terminal 3 of voltage follower U1 and the arc in phase on its in-phase input end 1, and voltage follower
The amplification factor of U1 is approximately 1, and therefore, the signal that the output terminal 3 of voltage follower U1 exports is the square-wave signal, described
Square-wave signal drives the first MOSFET Q1 to sequentially turn on and end, so as to which VRM200 generates one dynamically on load resistance R0
The output current Io of electric current, i.e. VRM200.
According to the resolution of operational amplifier, the electric current of the inverting input 2 of voltage follower U1 is approximately zero, because
This, the pressure drop very little on current-limiting resistance R5, the current potential on the source electrode s1 of the first MOSFET Q1 is approximately equal to voltage follower U1's
The current potential of inverting input 2.According to the short characteristic of void of operational amplifier, the current potential of the in-phase input end 1 of voltage follower U1 with
The current potential of inverting input 2 is equal, and therefore, the amplitude of the current potential on the source electrode s1 of the first MOSFET Q1 is believed equal to the square wave
Number amplitude.And the electric current on load resistance R0, the i.e. value of output current Io are equal to current potential and load resistance R0 on source electrode s1
Resistance value quotient, in this way, the amplitude by changing the square-wave signal, you can change the size of output current Io, so as in phase
In the case of the same rise time, output current Io is bigger, then its slope is bigger.Further, since the amplitude of the square-wave signal
During change, the amplitude of output current Io also changes correspondingly, and therefore, output current Io has the rising identical with the square-wave signal
Time, fall time, frequency and duty ratio by changing the rise time and fall time of the square-wave signal, also may be used
The corresponding rise time and fall time for changing output current Io, in the case where output current Io amplitudes are constant, the rise time
And fall time is bigger, then its slope is smaller.
In the present embodiment, load circuit 30 is drawn to further include NPN type triode Q2 and PNP type triode Q3.NPN type three
Pole pipe Q2 and PNP type triode Q3 avoids institute for enhancing driving force of the square-wave signal to the first MOSFET Q 1
Stating square-wave signal distortion can not the first MOSFET Q1 of normal driving.Specifically, the output terminal 3 of voltage follower U1 passes through current limliting
Resistance R5 is electrically connected to base stage b1, b2 of NPN type triode Q2 and PNP type triode Q3.The collector of NPN type triode Q2
C1 is electrically connected to+5V power supplys；Emitter e 1 is electrically connected to the emitter e 2 of PNP type triode Q3, and emitter e 1, e2 it
Between node the grid g1 of the first MOSFET Q 1 is electrically connected to by current-limiting resistance R3.The collector of PNP type triode Q3
C2 is electrically connected to -5V power supplys.In addition, when the first MOSFET Q1 end, PNP type triode Q3 is additionally operable to make first
Charging capacitor (not shown) in MOSFET Q1 is grounded rapidly electric discharge, so as to which the first MOSFET Q1 be made quickly to end, so as to carry
The response speed of high first MOSFET Q1.
Current detection circuit 40 includes operational amplifier U2, current-limiting resistance R6-R8 and feedback resistance R9.Operational amplifier
U2 includes in-phase input end 5, inverting input 6, output terminal 7 and control terminal 8.The in-phase input end 5 of operational amplifier U2 is logical
Cross the node that current-limiting resistance R6 is electrically connected between load resistance R0 and source electrode s1；And in-phase input end 5 and current-limiting resistance R6
Between node be also grounded by current-limiting resistance R8.Inverting input 6 is electrically connected to load resistance R0 by current-limiting resistance R7
Node between ground；And the node between inverting input 6 and current-limiting resistance R7 is also electrically connected to by feedback resistance R9
Output terminal 7.Output terminal 7 is electrically connected to master controller 10.Operational amplifier U2 on load resistance R0 for described in flowing through
Voltage signal is converted into after output current Io amplifications to export to the current detecting pin P1 of master controller 10,10 basis of master controller
The voltage signal accordingly calculates output current Io, so as to judge to export according to the variation of output current Io on load resistance R0
The slope of electric current Io.
Enabled circuit 50 is electrically connected to master controller 10, and master controller 10 is drawn by the enabled control of circuit 50 and carries circuit 30
And the working condition of current detection circuit 40.Specifically, it enables circuit 50 and includes the 2nd MOSFET Q4 and current-limiting resistance
R10.The grid g2 of 2nd MOSFET Q4 is electrically connected to the controlling switch P2 of master controller 10, source electrode s2 ground connection, grid d2 electricity
Property is connected to the control terminal 4,8 of voltage follower U1 and operational amplifier U2.The control of voltage follower U1 and operational amplifier U2
End 4,8 processed and drain electrode d2 between node a power supply is also electrically connected to by current-limiting resistance R10, as in present embodiment+
5V power supplys.Master controller 10 passes through the conducting and cut-off of the 2nd MOSFET Q4 of control, the corresponding level shape for changing control terminal 4 and 8
State, so as to which voltage follower U1 and operational amplifier U2 be controlled to start to work or be stopped.In the present embodiment, control terminal
4 and 8 be that high level is effective.In this way, when master controller 10 sends a low level signal (logical zero) to the by controlling switch P2
During two MOSFET Q4, the 2nd MOSFET Q4 cut-offs, control terminal 4 and 8 is connected to+5V power supplys and in height by current-limiting resistance R10
Level, voltage follower U1 and operational amplifier U2 start to work；And when master controller 10 is high by controlling switch P2 transmissions one
When level signal (logic 1) is to the 2nd MOSFET Q4, the 2nd MOSFET Q4 conductings, control terminal 4 and 8 passes through the 2nd MOSFET
Q4 is grounded in low level, and voltage follower U1 and operational amplifier U2 are stopped.
It is appreciated that the enabled circuit 50 can also be only connected to voltage follower U1 or operational amplifier U2 wherein
One, so as to which master controller 10 only controls the working condition of one of them of voltage follower U1 or operational amplifier U2
System.
In the present embodiment, the default slope value is inputted by the keyboard circuit 60 for being electrically connected to master controller 10.
Different default slope values is inputted by keyboard circuit 60, can so that load circuit 30 is drawn, which to obtain different drawings, carries slope.In addition,
The parameters such as amplitude, rise time, fall time, frequency and the duty ratio of the square-wave signal that function generator 20 exports
It can be inputted by the keyboard circuit 60, master controller 10 receives each parameter of the square-wave signal by keyboard circuit 60, and
The corresponding square-wave signal is exported according to each state modulator function generator 20.
Display 70 is electrically connected to the master controller 10, for showing keyboard circuit under the control of master controller 10
The default slope value of 60 inputs and each parameter of the square-wave signal.
The course of work of power source loads test device 100 described in brief description：
The drain electrode d1 of the first MOSFET Q1 for drawing and carrying circuit 30 is electrically connected to a tested power supply first, such as originally
VRM200 to be measured in embodiment.Then keyboard circuit 60 inputs the width of the default slope value and the square-wave signal first
The parameters such as value, rise time, fall time, frequency and duty ratio.Master controller 10 controls display 70 to show keyboard circuit
The above- mentioned information of 60 inputs, while the function generator 20 according to each state modulator of square-wave signal that keyboard circuit 60 inputs
The corresponding square-wave signal of output, subsequent master controller 10 are drawn by the enabled control of circuit 50 and carry circuit 30 and current detecting
Circuit 40 is started to work, and is drawn and is carried circuit 30 then according to the square-wave signal driving VRM200 corresponding output current Io of output, electricity
Then cooperation master controller 10 detects the variation of the output current Io accordingly to judge the output electricity to current detection circuit 40
Flow the slope of Io.The slope of the output current Io detected and the default slope value are compared by master controller 10 again, and
The amplitude of the square-wave signal and/or rise time and fall time are carried out according to comparison result control function generator 20 micro-
It adjusts, until the slope of output current Io is equal with the default slope value.
At this point, power source loads test device 100 can be equivalent to a dynamic electronic load, in power source loads test device
Under the action of 100 so that the output current Io of VRM200 is in dynamic change, realizes the dynamic test to VRM200.
The power source loads test device 100 is by 10 control function generator 20 of master controller to the wave of square-wave signal
Shape is adjusted, and the drawing so as to accordingly adjust the power source loads test device 100 by drawing load circuit 30, which carries slope, reaches it
To the default slope value, larger drawing load slope can be obtained so as to be arranged as required to the default slope value.In addition,
According to the different default slope values that keyboard circuit 60 inputs, the power source loads test device 100 can also accordingly obtain difference
Drawing carry slope, therefore, have preferable versatility.
Claims (7)
1. a kind of power source loads test device carries out dynamic load test for power supply tested to one, it is characterised in that：The electricity
Source load testing device includes the master controller being electrically connected successively, function generator, draws load circuit, current detection circuit, electricity
Property be connected to the master controller for inputting the default slope value of the keyboard circuit of default slope value and the display input
Display, the function generator for export a square-wave signal；Described draw carries circuit for being moved according to the square-wave signal
Change to state the output current of the tested power supply；The current detection circuit is also electrically connected to the master controller, described
Current detection circuit is used for the slope that the master controller is coordinated to detect the output current, and the master controller is used to detect
To the slope of the output current be compared with a default slope value, and the function is accordingly controlled to send out according to comparison result
Raw device adjusts the square-wave signal, until the slope of the output current is equal with the default slope value.
2. power source loads test device as described in claim 1, it is characterised in that：The master controller is by controlling the letter
Number generator changes (i) amplitude and/or (ii) rise time and the fall time of the square-wave signal to adjust the output
The slope of electric current.
3. power source loads test device as described in claim 1, it is characterised in that：It is described that load circuit is drawn to include voltage follow
Device, the first mos field effect transistor and load resistance, the in-phase input end electricity of the voltage follower
Property be connected to the output terminal of the function generator, for receiving the square-wave signal, the output terminal electricity of the voltage follower
Property is connected to the grid of first mos field effect transistor, first MOS field
The drain electrode of effect transistor is electrically connected to the output terminal of the tested power supply, first metal oxide semiconductor field-effect
The source electrode of transistor is grounded by the load resistance, and the source electrode of first mos field effect transistor
Node between the load resistance is electrically connected to the inverting input of the voltage follower.
4. power source loads test device as claimed in claim 3, it is characterised in that：It is described that load circuit is drawn to further include filter resistance
And filter capacitor, the inverting input of the voltage follower passes sequentially through the filter resistance and filter capacitor electrically connects
It is connected to the output terminal of the voltage follower.
5. power source loads test device as claimed in claim 3, it is characterised in that：It is described that load circuit is drawn to further include the first current limliting
Resistance, first current-limiting resistance are electrically connected to the inverting input of the voltage follower and first metal oxide
Between node between the source electrode of semiconductor field effect transistor and the load resistance, for preventing the voltage follower
Electric current on inverting input impacts the test of the output current.
6. power source loads test device as claimed in claim 3, it is characterised in that：It is described that load circuit is drawn to further include NPN type three
Pole pipe, PNP type triode, the first power supply and second source, the output terminal of the voltage follower are electrically connected to the NPN
The base stage of type triode and the PNP type triode, the collector of the NPN type triode are electrically connected to first electricity
Source；Emitter is electrically connected to the emitter of the PNP type triode, and the NPN type triode and PNP type triode
Node between emitter is electrically connected to the grid of first mos field effect transistor；The PNP
The collector of type triode is electrically connected to the second source；The NPN type triode and PNP type triode are used to enhance
The square-wave signal avoids the square-wave signal from being distorted the driving force of the first mos field effect transistor
It can not the first mos field effect transistor of normal driving.
7. power source loads test device as claimed in claim 3, it is characterised in that：The current detection circuit is put including operation
Big device, the in-phase input end of the operational amplifier are electrically connected to first metal oxide semiconductor field effect transistor
Node between the source electrode of pipe and the load resistance, the inverting input of the operational amplifier are electrically connected to the load
Node between resistance and ground, the output terminal of the operational amplifier are electrically connected to master controller, and the operational amplifier is used
Corresponding voltage signal is converted into after the output current flowed through on the load resistance is amplified to export to the master control
Device processed, the master controller accordingly calculate the output current according to the voltage signal, so as to according to the output current
The slope of the output current is judged in variation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610012915.3A CN105699913B (en) | 2012-06-21 | 2012-06-21 | Power source loads test device |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210206665.9A CN103513191B (en) | 2012-06-21 | 2012-06-21 | Power source loads proving installation |
| CN201610012915.3A CN105699913B (en) | 2012-06-21 | 2012-06-21 | Power source loads test device |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210206665.9A Division CN103513191B (en) | 2012-06-21 | 2012-06-21 | Power source loads proving installation |
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| Publication Number | Publication Date |
|---|---|
| CN105699913A CN105699913A (en) | 2016-06-22 |
| CN105699913B true CN105699913B (en) | 2018-07-06 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201610012915.3A Active CN105699913B (en) | 2012-06-21 | 2012-06-21 | Power source loads test device |
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| CN (1) | CN105699913B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113655400A (en) * | 2021-09-26 | 2021-11-16 | 西安易朴通讯技术有限公司 | Power supply testing method and tool |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791657Y (en) * | 2004-10-29 | 2006-06-28 | 山东大学 | Electric load general simulation device |
| CN2919266Y (en) * | 2006-06-30 | 2007-07-04 | 青岛艾诺电子仪器有限公司 | Direct current electronic loading device |
| CN102195479A (en) * | 2010-03-08 | 2011-09-21 | Nxp股份有限公司 | Controller for, and method of controlling, a switched mode power converter |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7176668B2 (en) * | 2004-07-08 | 2007-02-13 | Matsushita Electric Industrial Co., Ltd. | Switching regulator with advanced slope compensation |
| KR101045176B1 (en) * | 2008-12-04 | 2011-06-30 | 호서대학교 산학협력단 | Hysteresis current regulator using a slope of reference current |
-
2012
- 2012-06-21 CN CN201610012915.3A patent/CN105699913B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2791657Y (en) * | 2004-10-29 | 2006-06-28 | 山东大学 | Electric load general simulation device |
| CN2919266Y (en) * | 2006-06-30 | 2007-07-04 | 青岛艾诺电子仪器有限公司 | Direct current electronic loading device |
| CN102195479A (en) * | 2010-03-08 | 2011-09-21 | Nxp股份有限公司 | Controller for, and method of controlling, a switched mode power converter |
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Effective date of registration: 20180530 Address after: 410205 4, floor two, phase 18, Lu Yun Road, hi tech Development Zone, Changsha, Hunan. Applicant after: Boehner testing and Certification Co., Ltd. Address before: 518000 Room 201, building A, 1 front Bay Road, Shenzhen Qianhai cooperation zone, Shenzhen, Guangdong Applicant before: Nine city network technology (Shenzhen) Co., Ltd. |
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